1. Field of the Invention
This invention relates to a digital broadcast receiver unit, and in particular, relates to a digital broadcast receiver unit capable of receiving, in one stream, multiplex video signals formatted according to a plurality of differing scanning methods.
2. Description of Related Art
In digital transmission technology, in addition to video and audio signals, all kinds of information can be multiplexed and broadcast over one common carrier wave, i.e., multi-channel broadcasts utilizing this technology have already commenced. By utilizing this digital transmission technology, video signals for different scanning methods can be coded, multiplexed (i.e., placed on one common carrier wave) and then broadcast.
In contrast, in related art analog broadcast receivers, television receivers are able to receive transmissions from a plurality of analog broadcast systems. In analog broadcasting, however, different kinds of information cannot be multiplexed (or placed together on the same carrier wave) so that the received video signal itself must be analyzed to determine the scanning method. When receiving different video signals having a plurality of scanning systems in the above mentioned related art analog broadcasts, not only was a custom identification means required to analyze and process the received video signal itself, but in order to identify the video signal, video signal processing circuits had to be operated whose operation was not actually necessary.
In contrast, one important feature of digital broadcasting, however, is that a plurality of information such as audio, video and data can be multiplexed and sent as one transmission stream. Utilizing multiplexed data therefore means that various features can be provided.